My 95 yukon 4.3 liter has no brain,,,needin help.

[3 rings rob]

I recently purchased a 95 Yukon with 4.3 Ltr. Running a little rough and idling even worse. Changed PVC Valve, all new vac. hoses. Not much difference. The strong smell of fumes told me the fuel pump was good. The Service engine soon light comes on only when you turn on the ignition, so bulb isn't burned out. had it anlyzed by a professional, no communication could be made. With new brain installed we still could not make contact with it. So my Yukon is brain dead, much like his owner. Any ideas?


Thanks for ahead
RS

[maxwedge]

It is possible the powered up terminal at the link for the scanner is dead, did the scanner lite up or just no comm, info is lite here.

[3 rings rob]

Maxwedge, Thank you for the reply. I was standing right beside the man but did not look at the scanner. Friday I will stop by and ask him for the info. The Service Engine Soon light not coming on, would it be related to this also?

Thanks again

3 rings rob